Signaling system control



8- 1934- A. H. TAYLOR 1,969,335

' SIGNALING SYSTEM CONTROL Filed May 9, 1929 IN V EN TOR (M6441 3C, 5 I 04/,

B wa J 3 TTORNEY Patented Aug. 7, 1934 1,969,335 sIGNALmG-sYsTEMooNrRo Albert H. Taylor, Washington, 0., assignor to pWired Radio, Inc., New York, N.; Y., a corporation of Delaware Application-May 9, 1929 ,-{Seri al No. 361,714

4 Claims. (01. 250-17) My invention relates broadly to signaling systems, and more particularly tor arrangements' for controlling the output of signaling systems.

One of the objects of my invention is to pro- *vide an arrangement whereby the output of a signaling system employing frequency controlling and stabilizing devices maybe readily and efficiently controlled. c

Another object of my invention is to provide an arrangement for controlling the output of signaling systems employing a source of substantially constant frequency oscillations and a system of amplifiers for increasing the ampli- ,tude of the oscillations.

Still another object of my invention is toprovide an arrangement for controlling the output of a signaling system-employing a source of high frequency oscillations'and an amplifier sysv .,tem, having at least one electron discharge device of the normally positively charged auxiliary grid electrode type, for increasing the amplitude of the high frequency oscillations derived from the high frequency oscillation source, in

which arrangement the signaling system output controlling elements cooperate with the auxiliary grid electrode ,of the electron discharge device connected into the amplifier system. I

A further object of my invention is to pro- .vide an arrangement for controlling the out- 'put of a signaling system employin'g'a source of high frequency oscillations, a frequency changing system for derivinga signaling frequency bearing a harmonic relation to the'high frequency oscillations derived from the source,

and an amplifier system for increasing the amplitude of the oscillations impressed upon the circuits thereof, the amplifier system having at.

least one electron discharge device which is provided with an auxiliary grid electrode that is normally positively charged, with which auxiliary grid electrode the signaling system output control elements are operatively associated.

Other objects and features of my invention will be more fully understood from the following specification and by reference to the accompanying drawing. 1

In signaling systems employing a source ofsubstantially constant frequency oscillations for controlling the frequency of the system, one

or more electron discharge devices are ordinarily employed as amplifiers for increasing the amplitude of. the oscillations and where the signaling system is employed for high frequency communication on frequencies differing from the frequency ofthe sourcei- Usually one 'or more electron discharge devices are employed for deriving oscillations bearing a harmonic relation to the oscillations derived from the source.

Difficulty is usually encountered in attempting to vary the output of a signaling system, em-

ploying a plurality of electron discharge devices, in accordance with a certain pattern for the transmission of intelligence, where the mode of control consists in the impressing of a high negative potential on thecontrol grid electrode of an electron discharge device employed in the system and blocking the operation of the electron discharge device, since a relatively high voltage is ordinarily required to block the operation of the electron discharge device in this man-.

ner. According to my invention the signaling system output control arrangement is connected with a shield grid electrode of one of. the electron discharge devices employed in the amplifier unit of the system. I employ an arrangement whereby a positive potential of the proper magnitude is impressed upon the shield grid or auxiliary grid electrode of one of the electron discharge devices employed in the amplifier unit when it is desired to cause the whole amplifier to function to increase the amplitude of the signaling oscillations derived from the source of high frequency oscillations associated with the amplifier unit. When it is desired to interrupt the transmission of signaling oscillations through the amplifier unit, the shield grid electrode of the shield grid electron discharge device employed in the amplifyer unit is caused to assume either the ground potential or the po tential of an electrodewhich is practically isolated from the external circuits of the electron discharge device. Thus it is possible to block the electron stream in that particular electron discharge device.

In practice, the shield grid electrode substantially surrounds the anode completely and results in eliminating the coupling between the control grid and the anode, which permits the I tube to be automatically balanced without the "use of specially balanced circuits. I

In the system of my invention the transmission of signalling oscillations may be interrupted.

either in the electron discharge device imme' diately] following the source of high frequency oscillations, that is, the electron'dischargede lO5 vice having its input circuit coupled to; the

output circuitof the source of high frequency oscillations, or many successive electron dis-. charge device employed as an amplifier..

In the drawing, Figure 1 illustrates one em 110' bodiment of my invention and Fig. 2 illustrates another embodiment of my invention.

Reference numeral 1 of Fig. 1 of the drawing, designates a source of substantially constant frequency oscillations including an electron discharge device 2, a piezo electric crystal element 3 and'an output circuit 4. Where it is desired, a magnetostriction type of electromechanical vibrator element may be employed in place of the piezo electric crystal elementJ Another elec-v tron discharge device 5 having an anode 5a, a

grid electrode 51), a cathode 5c, and an auxiliaryshielding grid electrode 5d is connected with the output circuit 4 of the source 1. A condenser 6 is connected to the inductance 4a ofthe output circuit 4 and the grid'electrode 53b for coupling the electron discharge device '5 to the circuit 4. A choke coil 7 is connected to the source of grid biasing potential 8 and the gridelectrode 51). A source of anode current 9, having'a radio frequency by-pass condenser 10. connected in parallel'with it, is connected to the inductance 11 and the condenser 12. V

I-he inductance 11 and the capacity 12 form the' output circuit of the electron discharge device- 5; Connections areprovided between the anode 5a and the output circuit comprising the inductance 11 and capacity 12. A condenser '13 is provided between the auxiliary grid electrode 5d and the cathode 5c of the electron discharge device 5 for substantially reducing the radio frequency potential of the auxiliary grid electrode'5d, Under normal operating conditions when the key 14 is depressed the Winding of the gs relay-lfi is energized from the source 15 and 'the circuit between the auxiliary grid electrode 5d and the positive terminal of the source 9 .is established through the resistance 1'7. electron discharge device 5 then functions as 4Q an amplifierand signaling energy is transmitted through'the-output circuit including the induc tance 11 and'the capacity 12 to the circuit of the antenna 2 0; When the key 14 .is released the circuit'of the winding of the relay 16'is deenergized, therebyinterrupting the circuit which exten'dedfrom sources, through resistance 17-, and "contacts of relay 10 to the auxiliary grid electrode'Sd. The impedance of the electron discharge 1 device 5- Tie, therefore, greatly ing creased by the condition of an insufficient positive potentialon the auxiliary grid and the signaling energy transmitted to the antenna 20 is interrupted. v

Anabsorption circuit comprising the resistance 18 and the capacity 19 is provided across the contacts of the relay 16 in order to reduce thexspar-king that may take place at these contacts."' The'contacts of the relay are thus pre-' vented from excessive burning and better transmission of interrupted signals is obtained from 'the. system. c

I-nEig. 2 a modified form of" my invention is illustrated in which the circuit between the cathode'fic, which is maintained at or approximately at'groun'd potential, and the auxiliary grid electrode 511 is interrupted through the operation of the relay 16 and a positive potential is. impressed upon the auxiliary grid electrode 5dfrom thesource 9 through theresi'stance 21.. 7c The auxiliary-grid electrode 5d is permanently connected to, the "positive terminal of the source 9 e i e res st nc 2. T p si ve p tens tial frorn source 9 is applied to the grid electrode 5d only under the condition existing when relay fit, 16 is energized and its contacts are opened, as

The

grid electrode, soas to interrupt the transmission of-signaling energy to the antenna 20, the

same as was described with respect to Fig. 1.

The cperation or" the device 5 is thus readily controlled by manipulating the key 14. The operation of't he source ofjhigh frequency oscillations 1 is notint'e'rrupted' or disturbed in controlling the output ofthe'system for the transmission of signals. Once the source 1 is adjusted to maximum output and efliciency, it is not necessary to interrupt its operation in order to utilizethe signaling oscillations intermittently for transmission of code signals. e

It is, of course, to be'understood' that any convenient sourceof current supply, such as a moto'r generator set, battery ;or rectified alternating current source may bej ernployed as each of It is. also to be understood thatthe electron discharge devicel5 with which the'output control arrangement including relay 16, source of current 15 and key 141, is'associatedi need not necessarily be coupled directly to the output circuit of the source of high frequency oscillations 1, but that otherarnplifying and/or frequency changing electron discharge. devices may be connected into-circuit between the device 5 nd e Source Qt er e ectro d schar e devices may so be conn cted to. the output cir-. cult of device 5 where itilS desired to further increase the amplitude of the high frequency oscillations before impressing them on a transmission circuit or antenna.

Other modifications of '-my invention may be made without departing from the spirit andscope thereof audit is therefore to be under stood that I do not desire'to limit 'my invention to the details as set forth in the foregoing speci- 'ficationexcept in so far as these details are defined by the appended claims. 7

What I claim as new and desire to secure by Letters Patent of the United States isasfollQwsz 1. In combination, an electron discharge device vhaving a cathode, an anode, a grid electrode and an auxiliary grid electrode, input and output -circuits coupled to selected electrodes of said electron discharge device, means for im- 7 pressing electrical oscillations upon S id input circuit, a sourceof direct current supply for said anodel connected with the output circuit of said electron discharge device, connections be-.

een sa d au i l ri l c ode and said source of direct current supply for said anode r s pp ng o sa au i r d. a b s; positive with respect to said cathode, circuit estabh n errupting appa a us connected with, h irc s f a d au l arr gr electrode for controlling the operation of said electron.

discharge, d ce-said c cu t establishin andinterrunting. a pa b n rran ed t press apotenti'al correspondin to, the potential-i 0f th ca h d w en t s desi d te l ck the tr n t m: in saideleetm di char e device,

d. n a pti n Pa h. e ma n y .o.r i-ected;v

in parallel with said circuit establishing and interrupting apparatus.

2. The combination in accordance with claim 1 in which said absorption path includes a resistance and capacitance connected in series.

3. The combination in accordance with claim 1 in which said means for impressing electrical oscillations comprises a piezo-electric crystal controlled electron tube oscillator and in which 

